Subcaliber training cartridge



Sept. 8, 1959 M. MOLDOFSKY L SUBCALIBER TRAINING CARTRIDGE Filed Aug.25, 1958 on /1 6742 2/ w III. III- Unite States Patent ill SUBCALIBERTRAINING CARTRIDGE Matthew Moldofsky, Philadelphia, Pa., C WaltonMusser, Beverly, Mass, and Albert M. Stott, Aldan, Pa, as= signors tothe United States of America as represented by the Secretary of the ArmyApplication August 25, 1958, Serial No. 757,165

2 Claims. (Cl. 102-41) (Granted under Title 35, US. Code (1952), see.266) The invention described herein may be manufactured and used by orfor the Government for governmental purposes without the payment of anyroyalty thereon.

This invention relates to subcaliber training cartridges and has for itsprincipal object the provision of an improved mechanism whereby troopsmay be trained in the use of major weapons such as recoilless rifleswithout the expense incident to the use of the ammunition normally usedby such weapons.

It is desirable in the use of subcaliber training ammunition in a majorweapon that (1) the subcaliber ammunition be such as to require nomodification of the major weapon (2) the firing of the subcaliberammunition produce in the vicinity of the major weapon conditionssimilar to those produced by the firing of the major ammunition, and (3)the trajectory of the subcaliber projectile match that of the majorprojectile.

The present invention accomplishes all these results and, in additionprovides a minor caliber casing extractor which is actuated by a simplerotary movement of the rear end of the subcaliber mechanism.

The invention will be better understood from the following descriptionwhen considered in connection with the accompanying drawings and itsscope is indicated by the appended claims.

Referring to the drawings:

Fig. 1 is a longitudinal sectional view of the improved subcalibertraining cartridge which has outward dimensions similar to those of thecartridge normally fired by the major weapon,

Fig. 2 is a cross-section taken on the line 2-2 of Fig. 1, Fig. 3 is alongitudinal view of the subcaliber barrel, and

Fig. 4 illustrates a detail of the subcaliber barrel.

The subcaliber training cartridge of Figs. 1 and 2 includes a casingwhich has perforations 11 and encircles a subcaliber rifle barrel 12.Threaded onto the barrel 12 i-s'a barrel adjusting nut 13 which has aplurality of circumferentially arranged apertures. Into one of theseapertures is threaded a locking screw 14. Into the remainder of theseapertures are threaded special screws 15 which are backed outward fromthe apertures to fix the casing 10 to the barrel 12. With the screw 14in its untightened position, the casing 10 and the nut 13 may be rotatedfor adjusting the casing longitudinally of the barrel.

At its rear end, the barrel adjusting nut 13 engages a bearing 16 towhich it is coupled by pins 17 which extend through the rear end of thenut 13 into a circumferential groove 18 of the bearing. This couplingpermits rotation of the bearing with respect to the nut which isnormally fixed to the barrel and casing.

The bearing 16 has a longitudinal slot 19 in which is located asubcaliber casing extractor 20 biased to its illus- Patented Sept. 8,1959 2 trated position by a spring 21. The extractor has at its forwardend a tang 22 and at its rear end a stop 23 which is adjacent acam-shaped surface 24.

As shown more clearly in Figs. 3 and 4, the barrel 12 has a thread 25.This thread, extending about threefourths of the way around the barrel,is cut in a raised section 26 of the barrel, and is arranged to receivethe tang 22 of the extractor. Under these conditions, rotation of thebearing 16 moves the tang in the groove 25 and forces the extractor tothe rear. As the extractor moves to the rear, the cam-shaped surface 24engages the offset in the barrel and the rearward motion is arrested bythe stop 23 engaging this offset. There is thus produced a rearward andslightly outward movement by which the minor caliber casing isextracted. Upon rotation of the bearing in the opposite direction, theextractor is returned to its illustrated position.

At its forward end, the barrel 12 is positioned within a nose 27 bymeans of a sleeve 28, a ring 29 pressed into the shell body and screws30 and 31. The screws 30 are utilized to adjust the barrel to a desiredposition within the casing and the screws 31 function to lock the screws30 in the position to which they are adjusted.

Intermediate its ends, the barrel 12 has a series of small holes 32which, taken with the openings 11 of the casing, produce a realisticflash from the rear of the major Weapon. This not only trains thepersonnel in the handling and firing of the round. It gives them therealistic flash that warns them to stay away from the rear of allrecoilless rifles when they are fired.

The holes 32 have the effect of reducing the velocity of the minorcaliber projectile and are so proportioned as to match the trajectory ofthis projectile with that of the major projectile. These holes thusserve the double function of producing a realistic rearward blast and ofimparting a desired trajectory to the subcaliber projectile.

We claim:

1. In a subcaliber training cartridge having a perforated casing whichhas a diameter commensurate with the bore of a major weapon, thecombination of a subcaliber barrel extending into said casing and havingrelatively fine and coarse threads, means for locking said barrel tosaid casing, a barrel adjusting nut threaded onto said fine thread, abearing rotatably coupled to said nut and having a longitudinal groove,and an extractor located in said groove and having a tang arranged toengage said coarse thread for moving said extractor in said groove.

2. In a subcaliber training cartridge having a perforated casing whichis of a diameter commensurate with the bore of a major weapon and hascircumferentially arranged openings near its rear end, the combinationof a subcaliber barrel extending into said casing and having relativelyfine and coarse threads, a barrel adjusting nut threaded onto said finethread and having front and rear circumferentially arranged apertures, aplurality of screws each threaded into a different one of said frontapertures for locking said casing to said barrel, a bearing havingcircumferential and longitudinal grooves, a plurality of pins eachextending through a diiferent one of said rear apertures into saidcircumferential groove and an extractor located in said longitudinalgroove and having a tang arranged to move in said coarse thread inresponse to rotation of said bearing.

References Cited in the file of this patent UNITED STATES PATENTS2,826,145 Sandberg et a1. Mar. 11, 1958

